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Abstract : Growth of Magnesium Oxide Thin Films Using Molecular Beam Epitaxy
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Abstract: Ultra thin MgO films (1-2 nm) are grown on Si/SiO2 substrates using molecular beam epitaxy (MBE). Different growth conditions such as substrate temperatures, annealing conditions and growth rates are tested in order to achieve optimum parameters for the smooth and uniform growth. The films were characterized ex-situ using atomic force microscopy and x ray diffractio. Our results demonstrate MBE growth of MgO films with an rms roughness better than 0.5 nm on Si/SiO2 substrates. These results are important for the applications of MgO films as tunnel barriers in spintronic devices. Keywords: Ultra thin films, MgO, molecular beam epitaxy (MBE), atomic force microscopy (AFM), X-ray diffraction (XRD). |
Abstract : Impact of Project Complexity and Environmental Factors on Project Success: A Case of Oil and Gas Sector of Pakistan
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Abstract: Oil and gas industry significantly contribute for economic development of countries enriched with petroleum resources. Mega projects of oil and gas sector usually face many challenges due to environmental issues, high level of risks, huge investments, tight schedules and interdependencies between project activities. Therefore keeping in view, the issues faced by oil and gas sector this study was made to analyze the impact of project complexity and environmental factors on success of oil and gas projects of Pakistan. Based upon hypothetical framework developed for this study, data collection was made from an oil and gas company of Pakistan. After which, data analysis was carried out by using a statistical technique known as structural equation modeling. Project complexity, environmental factors and project success were taken as constructs for model evaluation on AMOS. Analysis of data has concluded that project complexity has negative impact on project success whereas better control over environmental factors enhance the project success rate. Keywords: Oil and gas projects, Project complexity, Environmental factors, Structural equation modeling. |
Abstract : Evaluation of M2 Wheat (Triticum aestivum L.) Mutants for Yield and its Contributing Traits
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Abstract: The present research was conducted to evaluate the M2 wheat mutant population for yield and its contributing traits. The experiment was conducted at Nuclear Institute of Agriculture (NIA), Tando Jam, during rabi season 2015-2016, in split plot design with three replications. Two wheat varieties (T. D-1 and ESW-9525) were treated with different levels of gamma rays (150Gy, 200Gy, 250Gy, 300Gy and control) from NIMRA (Nuclear Institute of Medicine and Radiotherapy), Jamshoro. The mutated plants were evaluated along with parental lines (control) for yield and its contributing traits under field conditions. Genetic parameters viz., mean performance, were calculated such as days to 75 % heading, days to 75 % maturity, plant height (cm), spikelets spike-1 and spike length (cm). Mean square showed that there were significant differences between wheat varieties for days to 75% heading, days to 75% maturity, plant height (cm), spikelets spike-1 and spike length (cm) treatments of gamma radiation caused significant variation in all the traits studied. The interaction between treatments × varieties showed highly significant differences for the entire traits indicating that varieties responded differently for radiation treatments. Mean performance for spike length indicated that the longer spike (11.52 cm) was observed in T.D-1 at treatment four (T4=250 Gy) and treatment two (150 Gy) in ESW-9525 . Whereas, the shortest spike (10. 83 cm) was observed in the variety T.D-1 under control. The results regarding maximum mean performance of spikelets spike-1 (24. 74) were recorded in ESW-9525 under treatment five at 300 Gy whereas the minimum value for spikelets spike-1 (18.76) were observed in T.D-1 under T1 (18.76) at 0 Gy and T4 at 250 Gy. Keywords: Wheat, Mutation, Mutant, Population, Yield. |
Abstract : Assessment of Drinking Water Quality Status and its Impact on Health in Tandojam City
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Abstract: Unsafe drinking water is one of the major concerns in developing countries. The southern Sindh is province of Pakistan that adjoins the Arabian Sea coast where the drinking water quality is deteriorating due to unrefined urban waste and excessive use of agro-chemicals. Present study aimed to assess the quality of ground water source and to compare it with WHO standards. Water borne diseases associated with drinking it in the vicinity Tandojam city were identified. Water from ground water source was sampled at selected locations in the study area. The samples were collected mostly from pumped waters. The samples were analyzed for physico-chemical properties in order to identify the quality problems and suggest safe source for drinking purpose. Findings revealed that the ground water quality in Muzaffrabad colony is deteriorating. The situation was much worse in Muzaffrabad colony, Jam Ghar and Mir colony with high TDS and salty taste, respectively at few sampling locations. In addition, laboratory analysis of the water quality parameters revealed the detail of variation in the groundwater. TDS, hardness, sodium (Na), chloride (Cl) and magnesium (Mg) etc. were considerably beyond the WHO permissible limits. The poor quality of the water has created different waterborne diseases like cholera, diarrhea etc. Moreover, the samples of SAU Colony and Amar Town showed that the water quality of these areas was within acceptable limits according to WHO standards and was suitable for the purpose of drinking. Keywords: Drinking water quality, physico-chemical parameters, Tandojam city, waterborne diseases, WHO standards. |
Abstract : Effects of Fe-Doping on the Structural and Magnetic Properties of Indium Oxide Nanoparticles Synthesized by Bottom up Technique
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Abstract: We study Fe doped In2O3 nanoparticles (NPs) from structural and magnetic point of view. X-ray diffraction (XRD) and transmission electron microscopy (TEM) reveal cubic bixbyite structure for both pure and Fe doped samples thereby confirming successful incorporation of Fe in host In2O3 lattice. Average crystallite size of pure and Fe doped (5% and 10%) In2O3 as calculated by Scherer’s formula shows slight increase from 21 nm for pure to 27 nm for the sample with 10% Fe content. The Williamson Hall (WH) method was also utilized to further determine crystallite size and Fe induced strain in In2O3 lattice. The crystallite sizes by WH plot are found to be 18 nm (for undoped), 22 nm (for 5% Fe) and 24 nm (for 10% Fe). These values are in good agreement with TEM results. Energy dispersive x-ray spectroscopy (EDX) indicates the existence of some oxygen vacancies in Fe doped In2O3 samples. Magnetic measurements show that all Fe doped In2O3 NPs exhibit typical ferromagnetic hysteresis loop with saturation magnetization Ms increasing with increasing Fe concentration. Temperature dependence of field cooled (FC) and zero field cooled (ZFC) magnetizations show no divergence and transition from ferromagnetism to paramagnetism in the temperature range of 5 to 300 K. This evidences a robust room-temperature-ferromagnetism (RTFM) in these NPs. The RTFM of our samples is attributed to the presence of oxygen vacancies in our samples. Keywords: DMS, nanoparticles, defect states, magnetic property, X-ray diffraction. |